Related Articles

Even better news: Texas A&M University System entomologists have completed a survey that detected the protozoa in fire ant colonies in approximately 120 of the 157 Texas counties where they have been found.

Once a colony is infected, the protozoa debilitates the queen, the workers and even the larvae. The disease shortens their the ants' life spans and raises the mortality of sexual females. The tiny microorganism may not eradicate the fire ants but it has the potential of changing it from a highly aggressive pest into one much less competitive with native species, said Dr. Forrest Mitchell, entomologist with the Texas Agricultural Experiment Station at Stephenville.

Now that the survey is complete, the next step is to grow the protozoa on culture mediums. If culturing is successful, the research might eventually yield a product that would introduce the protozoa into fire ant mounds in the form of a bait. Alternately, infected fire ants might be introduced into areas where the protozoa is not present.

But there are a lot of questions to be answered and problems to be solved first.

The first question, Mitchell said, is where did the protozoans come from?

Though there are several native species of fire ant, their stings pale compared to their more aggressive cousin, the red imported fire ant, which was accidentally introduced to the United States in the 1930s. Because it lacks natural predators here, the red imported fire ant has spread to all or portions of Florida, Georgia, South Carolina, Tennessee, Alabama, Mississippi, Arkansas, Texas and Oklahoma. The species has become very abundant, displacing many native ant species.

Scientists have long known that one of the pest's natural enemies in South America is Thelohania solenopsae, a microscopic organism related to the amoeba.

"It infects about 25 percent of the ants down there. It is one of the natural pathogens, but the degree of its importance is hard to access," Mitchell said.

The scientific community has been extremely cautious about introducing the protozoa in the United States, however, not knowing what effect it might have on the native ant species, such as harvester, carpenter and leaf-cutting ants, Mitchell said.

Because of these fears, studies of the South American protozoa were done in labs under controlled conditions. Then in 1998, an U.S. Department of Agriculture entomologist found an fire ant colony near Thorndale infested with the protozoa.

"Later, tests showed that the DNA of the Thorndale strain differed from the South American strain," Mitchell said.

The Texas A&M survey shows the protozoa has occurred naturally, without human intervention. Questions still remain, however, before Mitchell is comfortable with the idea of helping the protozoa propagate. It could be that the protozoa was in North America all along, just waiting for the fire ant to be introduced as a host? Or, was the protozoa itself an emigre, hitching into the country with the South America fire ants? If it was an emigre, did the protozoa evolve so its DNA now looks different from that of the South American strain?

If the protozoa is native to North America, then its further introduction will not likely harm the native ant population. They are already adapted to it.

If it's not native,, helping it spread might not be a wise thing to do, Mitchell said. These are crucial questions because ants play a critical role in the ecological balance. The predatory types kill and eat many other insects, both harmful and beneficial. Though small individually, collectively ants can make a huge impact. Worldwide, a figure for ants comprising 15 percent of all terrestrial animal biomass is not out of line.

"No one really knows for sure what percentage ants constitute of the animal biomass. But one thing is for certain. If you really want to disrupt the ecosystem, disrupt the ants," Mitchell said.

More From ScienceDaily

More Plants & Animals News

Featured Research

Mar. 3, 2015 — New assays can detect malaria parasites in human blood at very low levels and might be helpful in the campaign to eradicate malaria, reports a new study. An international team led by Ingrid Felger, ... full story

Mar. 3, 2015 — While studying a ground-nesting bird population near El Reno, Okla., a research team found that stress during a severe weather outbreak of May 31, 2013, had manifested itself into malformations in ... full story

Mar. 3, 2015 — The 3-D printing scene, a growing favorite of do-it-yourselfers, has spread to the study of plasma physics. With a series of experiments, researchers have found that 3-D printers can be an important ... full story

Mar. 3, 2015 — Most people consume more salt than they need and therefore have a higher risk of heart disease and stroke, which are the two leading causes of death worldwide. But a new study reveals that dietary ... full story

Mar. 3, 2015 — By examining the forces that the segments of mosquito legs generate against a water surface, researchers have unraveled the mechanical logic that allows the mosquitoes to walk on water, which may ... full story

Mar. 3, 2015 — Pediatric otolaryngologists and surgeons are concerned with parents getting the wrong message regarding the safety/desirability of letting babies and young children eat peanuts to prevent them from ... full story

Mar. 3, 2015 — Researchers have developed a new way of rapidly screening yeasts that could help produce more sustainable biofuels. The new technique could also be a boon in the search for new ways of deriving ... full story

Mar. 3, 2015 — Similar to humans and animals, plants possess an innate immune system that protects them from invading pathogens. Molecular structures that only occur in pathogens enable their recognition and ... full story

Mar. 3, 2015 — For almost a century, scientists have been puzzled by a process that is crucial to much of the life in Earth's oceans: Why does calcium carbonate, the tough material of seashells and corals, ... full story

Featured Videos

Rare Goblin Shark Found in Australia

AFP (Mar. 3, 2015) — A goblin shark, a rare sea creature described as an &apos;alien of the deep&apos; is found off Australia and delivered to the Australian Museum in Sydney. Duration: 01:25
Video provided by AFP

Zookeepers Copy Animal Poses In Hilarious Viral Photos

Buzz60 (Mar. 2, 2015) — Zookeepers at the Symbio Wildlife Park in Helensburgh, Australia decided to take some of their favorite animal photos and recreate them by posing just like the animals. Jen Markham (@jenmarkham) has the story.
Video provided by Buzz60

Related Stories

Aug. 6, 2014 — When the ants come marching in, having miles of linked habitats may not be such a good idea after all. In a classic example of the law of unintended consequences, new research suggests that wildlife ... full story

Feb. 13, 2014 — Invasive "crazy ants" are rapidly displacing fire ants in areas across the southeastern US by secreting a compound that neutralizes fire ant venom, according to a new study. It's the ... full story

Nov. 26, 2013 — Fire-ant rafts aren’t just unusual in that they’re “viscoelastic,” like Jell-O and toothpaste, according to a new study. Researchers found the rafts actively reorganize their structure, a ... full story

May 16, 2013 — Invasive "crazy ants" are displacing fire ants in areas across the southeastern United States, according to researchers at The University of Texas at Austin. It's the latest in a ... full story

Feb. 24, 2011 — Red imported fire ant invasions around the globe in recent years can now be traced to the southern US, where the nuisance insect gained a foothold in the 1930s, new research has ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.